US Patent 8713972 Precision glass roll forming process and apparatus

A process and apparatus for precision glass roll forming a supply of molten glass at a glass temperature of 1000° C. or higher. A pair of hot forming rolls having a surface temperature of about 500° C. or higher, vertically below the glass feed, that thin the supplied stream of molten glass to produce a formed glass ribbon. A pair of cold sizing rolls maintained at a surface temperature of about 400° C. or lower, vertically below the forming rolls, that thin the formed glass ribbon glass to produce a sized glass ribbon having a desired thickness and a desired thickness uniformity. The sized glass ribbon may have a thickness of 1 mm or less that varies in thickness by no more than +/−0.025 mm.